This invention relates to a cooling arrangement for a multi-valve engine and more particularly to an improved cooling arrangement for the cylinder head of such an engine.
The advantages of multi-valve engines are well known. Although the efficiency and output of an engine can be increased by increasing the number of valves, the use of multiple valves gives rise to certain problems. One of these problems has to do with the configuration of the cooling jacket within the cylinder head. Normally the flow of coolant through the cylinder head is from end to end or across the cylinder head from one side to the other. However, in connection with the use of multiple valves and multiple ports an arrangement may result wherein a pocket is formed in the cooling jacket between the ports and circulation of coolant through this pocket is obstructed.
For example, it is frequently the practice to employ a pair of exhaust ports that extend through one side of the cylinder head with a spark plug well formed between these exhaust ports. Of course, it is also desireable to make the exhaust ports as large as possible and this restricts the area through which coolant may flow. In addition, the internal structure of the cylinder head may give rise to the formation of a wall that extends between the exhaust ports through the spark well and which precludes the flow of coolant from this well to the opposite side of the engine. As a result, hot spots can occur.
It is, therefore, a principal object of this invention to provide an improved cooling arrangement for a multi-valve engine.
It is a further objection of this invention to provide a cooling arrangement for a multi-valve engine wherein large valve ports may be accommodated and wherein the flow of coolant through the area between the valve ports is promoted.
It is a further objection of this invention to provide an improved arrangement for cooling the exhaust ports of a multiple valve internal combustion engine.